Thanks Bolocom and EvlPanda. I actually tried the clew first thing today as the wind was pretty well onshore. Only little toy waves, waist high grubbers, but I could see what ya saying about it changing the sail angle on the waves. All feels a little odd, but I got to go face-to-wave in cross to onshore conditions, which I would normally ride backhand. This has inspired me to wave sail more when the wind is a little "wrong". So cheers for that.
Whilst backhand is fun, face to wave is more funner